Lotion which is temporarily colored upon application

ABSTRACT

A lotion such as a sunscreen includes a pH indicator which colorizes the lotion until the lotion is applied to the human skin, whereinafter the colored lotion turns clear. A physiologically compatible pH indicator such as phenolphthalein is used which has a red appearance from pH 7.5+ and which has a clear appearance from about pH 7.0 to 7.5, the general pH range of the skin. The invention is suitable for use in any lotion, gel, mousse or medication that is best applied in an even and uniform manner to the skin. Accordingly, one preferred use of the invention is in UV-protecting sunscreens so that a user can ensure even distribution of the sunscreen on the body. In certain aspects of the invention, a cap houses the pH indicator and attaches to a container of the lotion, e.g., a sunscreen. The pH indicator mixes with the lotion as it is applied to the skin. The invention further provides methods of manufacturing sunscreens and the like with a pH indicator that turns substantially colorless upon prolonged contact with the skin.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuing application of commonly-owned and patentapplication Ser. No. 08/688,694, filed on Jul. 25, 1996, now U.S. Pat.No. 5,680,962 which is a divisional application of prior applicationSer. No. 08/340,540, filed on Nov. 16, 1994 (now U.S. Pat. No.5,567,420, issued Oct. 22, 1996), entitled "LOTION WHICH IS TEMPORARILYCOLORIZED UPON APPLICATION", each of which are hereby incorporated byreference.

BACKGROUND OF THE INVENTION

Darker skin pigmentation is considered desirable by many persons,socially and aesthetically. At present, the most common method fordarkening the skin is through sun-tanning, using either natural sunlightor specially designed ultraviolet (UV) light sources, e.g., tanninglamps.

However, extended exposure of human skin to ultraviolet light is knownto have adverse consequences, both in the short term and in the longterm. Specifically, in the short term, individuals exposed to UV risk apainful sunburn and keratitis. In the long term, extended exposure toultraviolet radiation can result in photo-aging and "leathery" skin, andcan further result in various forms of skin cancer and ultimately death.

Fair-skinned individuals are particularly susceptible to sun-inducedskin disorders and cancers. For example, they face a higher risk ofmelanoma (skin cancer), and often incur photo-aging or dermatoheliosis,a condition characterized by wrinkling, irregular pigmentation, andsurface roughness. However, even darker skinned individuals exposed toprolonged sunlight incur a high risk of skin cancer and exacerbatedaging.

These risks, together with the continued desirability of the suntanlook, have resulted in a wide range of UV protection suncreen agents.Such sunscreen agents are typically suspended in a cream, lotion, gel,mousses, waxed based sticks, aerosols, and alcohol sticks for topicalapplication to the skin. For example, the Coppertone™ Company makes alarge assortment of popular sunscreen lotions with varying degrees ofsun block which extend the body's normal resistance to UV radiation.

One important step in the proper application of an UV protectivesuncreen lotion on the body is the even and complete coverage of allbodily areas which are exposed to the sun. Typical suncreen lotions andthe like are applied as clear or white creams that are difficult to seeupon application. It is thus difficult for a user of these typicalsuncreen lotions to assure even and complete coverage on the body.Consequently, it is common to miss spots, resulting in an uneven tan orburn, and the increased susceptibility to the several risks discussedabove.

It is, accordingly, an object of the invention to provide a sunscreenagent which increases the likelihood of even and complete coverage whenapplied to the body.

Another object of the invention is to provide a UV protective sunscreenlotion which reduces the risks associated with improper application tothe body.

Still another object of the invention is to provide improvements tolotions, gels, mousses and creams that are applied topically to thehuman skin.

These and other objects of the invention will become apparent in thedescription which follows.

SUMMARY OF THE INVENTION

As used herein, "color indicator," "indicator," or "CI," includes thenaturally occurring and synthetic derivatives of pH indicators. A "pHindicator" is a compound that changes its visible color upon a change inpH (hydrogen ion concentrations). Suitable pH indicators according tothe invention include those indicators which are clear or colorless inthe pH range of approximately 6.5-8.0, and which are colored or visibleabove or below that pH range.

The present invention includes a method for applying and distributingsunscreens and lotions evenly. In one aspect of the invention, a colorindicator is added to such sunscreens or lotions for visual detection bya user of the sunscreen or lotion. The CI in the sunscreen or lotioncomposition initially has a visible color upon application to the skin,and changes or becomes clear (colorless) after a short time period(i.e., between about 0.5 and 10 minutes), thereby permitting the normalor unimpeded use of the product for its intended function (i.e., afterthe short time period, the user is not colored by the CI but rather hasa skin color appearance that normally results from application of anuncolored lotion or sunscreen). The presence of the visible color on theepidermis is indicative of the location and amount of compositionthereon, thereby enabling total coverage with, and even distribution of,the composition. In one aspect of the invention, such an evendistribution of sunscreen ointment results in uniform protection fromexposure to UV radiation.

The invention is next described further in connection with preferredembodiments, and it will be apparent that various additions,subtractions, and modifications can be made by those skilled in the artwithout departing from the scope of the invention.

BRIEF DESCRIPTION OF THE FIGURES

The present invention may be more easily and completely understood whentaken in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates a typical use of the invention;

FIG. 2 is a graph illustrating certain effects of indicatorconcentrations on the time course of CI change from visible to clear;

FIG. 3 is a graph illustrating certain effects of concentrations on CIchange from visible to clear when dissolved in a common sunscreen in tenvolunteers;

FIG. 4 shows a cap constructed according to the invention for adding aCI selectively to a lotion suitable for application on the body;

FIG. 4A illustrated further features of the cap of FIG. 4; and

FIG. 4B illustrates flow rate overlapping holes which are suitable foruse with the cap of FIG. 4 to control flow and color rate.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The present invention provides compositions for application to the skin,including a pH indicator and methods of their preparation, as well asapparatus for temporarily colorizing the epidermis.

The CI suitable for use in the invention are those CIs which arephysiologically compatible with the skin, and which readily dissolve increams and lotions. The CIs may be used individually or in combination.Suitable CIs are also those physiologically acceptable substances whichappear clear at a pH of between approximately 6.5 and 8.0, and whichappear colored at a pH outside this range. Suitable CIs also includethose substances listed in Table 1 hereto.

The invention utilizes the fact that the pH of normal human skin isbetween approximately 7.0 and 7.5 at any given time. Therefore, one CIaccording to the invention has (i) clear appearance at a pH in thenormal skin range of 7.0 to 7.5 and (ii) a colored appearance at a pHoutside this range. Typical sunscreen creams and sun lotions have a pHof 7.5 or above. Thus, if a CI is chosen which is red at pH 8.0, andthat CI is added to a lotion with a pH of 8.0, then the lotion willappear red. When applied to the skin, however, the skin's pH will shiftthe overall lotion pH from 8.0 to 7.0-7.2, and will thus change the CIfrom red to colorless.

Alternatively, a sunscreen or lotion according to the invention is onewhich (i) has a pH of approximately 6.5 (or less) and (ii) utilizes a CIwhich is colored at pH 6.5 (or less) and colorless at pH 7.0 to 7.5.Consequently, upon application to human skin, the initially coloredsunscreen or lotion pH will shift upwards, due to the skin's pH, toapproximately pH 7.0 to 7.5, and will thus become colorless at thattime.

Indicators according to the invention can be added during themanufacture or the formulation of the lotion, such as described below.Alternatively, by controlling the pH of the lotion, the CIs can also beadded after formulation.

As described above, suitable indicators according to the invention arethose which undergo a color change from colored to clear (i.e.,substantially colorless) at a pH range of 6.5-8.0, and which aresuitable for application to the human skin. Suitable indicators, forexample, include phenolphthalein, σ-cresolphthalein, thymolphthalein,quinazolinedione, and ethyl-bis ethanoate. A color indicator such asphenolpthalein, for example, changes color from visible to clear whenits pH changes from a pH that is higher or lower than 7.0-7.4 to a pH of7.0-7.4. Other indicators according to the invention, such as Coumarin,and dioxyxanthone, respond to pH changes by changing from a fluorescentcolor to clear. A more comprehensive description of the indicatorsaccording to the invention is provided below in Table 1.

In accord with one embodiment of the invention, CIs are employedtopically. For topcial use, it is desirable that a CI is dispersed in anemulsion of sunscreen or lotion and applied to the skin. For thispurpose, the CIs are intended to be admixed in a pharmacologicallyacceptable topical carrier such as a gel, an ointment, a lotion, or acream. Such carriers include, but are not limited to, water, glycerol,alcohol, propylene glycol, fatty alcohols, triglycerides, fatty acidesters, and mineral oils.

Sunscreening agents according to the invention include the UVA-type(typical UVA-type sunscreening agents include certain benzophenones anddibenzoyl methanes), the UVB type (typical UVB type sunscreening agentsinclude substituted para-aminobenzoates, alkyl esters ofpara-methoxycinnamate and certain esters of salicylic acid), or acombination of the two. Generally, the sunscreening agents are used inamounts effective to provide the desired level of protection against UVAand/or UVB radiation. For example, the sunscreening agents are generallyused in the amounts of about 2% to about 20% by weight of the totalcomposition, with about 5% to about 18% being preferred, and about 2% toabout 15% being most preferred.

Representative UVB-type sunscreening agents suitable for use with theinvention include, without limitation, the following:

(A) DEA methoxyinnamate (diethanolamine salt of p-methoxy hydrocinnamate), e.g., tradename BERNEL HYDRO from Bernel Chemical Co., Inc.

(B) ethyl dihydroxypropl PABA (ethyl dihydroxypropyl p-aminobenzoate),e.g., tradename AMERSCREEN R from Amerchol Corp.;

(C) glycerol PABA (glyceryl-p-aminobenzoate), e.g., tradename NIPAG.M.P.A from NIPA Laboratories Inc.;

(D) homosalate (Homomenthyl salicylate), e.g., tradename KEMESTER HMSfrom Humko Chemical;

(E) octocrylene (2-ethylhexyl-2-cyano-3,3-diphenylacrylate), e.g.,tradename UVINUL N-539 from BASF Chemical Co.;

(F) octyl dimethyl PABA (OCtyl dimethyl p-aminobenzoate, 2-ethylhexylp-dimethylaminobenzoate, Padimate O), e.g., tradenames AMERSCOL,ARLATONE UVB, and ESCALOL 507 from Amerchol Corp., ICI Americas, Inc.,and Van Dyk, respectively;

(G) octyl methoxycinnamate (2-ethylhexyl-p-methoxycinnamate), e.g.,tradename PARSO₋₋ MCX from Bernel Chemical Co., Inc., or Givauden Corp.;

(H) octyl salicylate (2-ethylhexy salicylate), e.g., tradename SUNAROMEWMO from Felton Worldwide, Inc.;

(I) PABA (p-amino benzoic acid), e.g., tradename PABA from EMIndustries, Inc. and National Starch & Chemical Corp., and tradenameNIPA PABA from NIPA Laboratories Inc.;

(J) 2-phenyl-benzimidazole-5-sulphonic acid (Novantisol), e.g.,tradename EUSOLEX 232 and NEO-HELIOPAN HYDRO from EM Industries, Inc.and Haarmann & Reimer Corp., respectively;

(K) TEA salicylate (triethanolamine salicylate), e.g., tradenamesSUNADROME W and SUNDROME G from Felton Worldwide, Inc.;

(L) 3-(4-methylbenzlidene)camphor or 3-(4-methylbenzylidene)boran-2-one,e.g., tradename EUSOLEX 6300 from EM Industries, Inc.; and

(M) etocrylene (2-ethyl-2-cyano-3,3"-diphenylacrylate), e.g., tradenameUVINUL N-35 from BASF Chemical Co.

Representative UVA type suncreening agents suitable for use with theinvention include, without limitation, the following:

(A) benzophenone-3 (2-hydroxy-4-methoxy-benzophenone), e.g., tradenameSPECTRA-SORB UV-9 and UVINUL M-40 from American Cyanamid Co. and BASFChemical Co., respectively;

(B) benzophenone-4 (sulisobenzone), e.g., tradename UVINUL MS-40 fromBASF Chemical Co.;

(C) benzophenone-8 (dioybenzone), e.g., tradename SPECTRA-SORB UV-24from American Cyanamid Co.;

(D) methyl anthranilate (methyl-O-aminobenzoate), e.g., tradenameSUNAROME UVA from Felton Worldwide, Inc.;

(E) benzophenone-1 (2,4-dihydroxybenzophenone), e.g., tradename UVINUL400 and UVASORB 2OH from BASF Chemical Co. and TRI-K Industries, Inc.,respectively;

(F) benzophenone-2 (2,2',4,4'-tetrahydroxy-benzohpenone), e.g.,tradename UVINUL D-50 from BASF Chemical Co.;

(G) benzophenone-6 (2,2'-dihydroxy-4,4'-dimethoxy-benzophenone0, e.g.,tradename UVINUL D-49 from BASF Chemical Co.;

(H) benzophenone-12 (octabenzone), e.g., tradename UVINOL 408 from BASFChemical Co.;

(I) 4-isopropyl dibenzoyl methane(1-p-cumenyl-3-phenylpropane-1,3-dione), e.g. tradename EUSOLEX 8020from EM Industries Inc.; and

(J) butyl methyl dibenzoyl methane (4-t-butyl-4'-methoxydibenzoylmethane), e.g. tradename PARSOL 1789 from Givaudan Corporation.

Physical sunscreening agents may also be added to the compositionaccording to the invention. For example, red petrolatum in amounts ofabout 30% to about 99% by weight of the total composition, or titaniumdioxide in amounts of about 2% to about 25% by weight of the totalcomposition can be used. Talc, kaolin, chalk, and precipitated silicacan also be used in effective amounts, e.g., about 1% to about 10% byweight of the total composition.

Additional sunscreening agents according to the invention includelawsone hydroxynaphthoquinone, C₁₀ H₆ O₃ (the coloring matter of hennaleaves) with dihydroxy acetone.

In accord with preferred embodiments of the invention, at least oneUVA-type or UVB-type sunscreening agent is preferably used incompositions designed to inhibit UV radiation. For example, thefollowing UVB-type sunscreening agents can be used according to theinvention: from about 1.5% to about 8.0% by weight of the totalcomposition of octyl dimethyl PABA; octyl para-methoxycinnamate inamounts of about 1.5% to about 7.5% by weight of the total composition;homomethyl salicylate in amounts of about 4.0% to about 15% by weight ofthe total composition; and octyl salicylate in amounts of about 3% toabout 5% by weight of the total composition.

In another embodiment, at least one of the following UVA typesunscreening agents can be added: benzophenone-3 in amounts of about0.5% to about 6% by weight of the total composition; benzophenone-8 inamounts of about 0.5% to about 3% by weight of the total composition;and menthyl anthanilate in amounts of about 3.5% to about 5.0% by weightof the total composition.

The color indicator compositions according to the invention can beincorporated into formulations such as lotions, creams, gels, mousses,waxed based sticks, aerosols, alcohol sticks and the like. Theseformulations are well known in the art. For example, informationregarding such formulatios may be found in (i) Balsam, M. S., andSagrin, E. (Editors) Cosmetics Science and Technology, Second Edition,Volumes 1 and 2, Wiley-Interscience, a division of John Wiley & Sons,Inc., New York, copyright 1972; and (ii) Flick, E. W., Cosmetic andToiletry Formulations, Noyes Publications, 1984, each of which isincorporated herein by reference.

In addition to the UV-blocking additives described above, lotions and/orsunscreens according to the invention can include other compounds,including any of the following: (i) emollients, (ii) emulsifiers, (iii)surfactants, (iv) waxes, (v) thickeners, (vi) film formers, (vii)preservatives, and (viii) perfumes.

Emollients

Emollients may be used according to the invention in amounts which areeffective to prevent or relieve dryness. Useful emollients include,without limitation: hydrocarbon oils and waxes; silicone oils;triglyceride esters; acetoglyceride esters; ethoxylated glyceride; alkylesters; alkenyl esters; fatty acids; fatty alcohols; fatty alcoholethers; etheresters; lanolin and derivatives; polyhydric alcohols(polyols) and polyether derivatives; polyhydric alcohol (polyol) esters;wax esters; beeswax derivatives; vegetable waxes; phospholipids;sterols; and amides.

Thus, for example, typical emollients include mineral oil, especiallymineral oils having a viscosity in the range of 50 to 500 SUS, lanolinoil, mink oil, coconut oil, cocoa butter, olive oil, almond oil,macadamia nut oil, aloa extract, jojoba oil, safflower oil, corn oil,liquid lanolin, cottonseed oil, peanut oil, purcellin oil,perhydrosqualene (squalene), caster oil, polybutene, odorless mineralspirits, sweet almond oil, avocado oil, calophyllum oil, ricin oil,vitamin E acetate, olive oil, mineral spirits, cetearyl alcohol (mixtureof fatty alcohols consisting predominantly of cetyl and stearylalcohols), linolenic alcohol, oleyl alcohol, octyl dodecanol, the oil ofcereal germs such as the oil of wheat germ cetearyl octanoate (ester ofcetearyl alcohol and 2-ethylhexanoic acid), cetyl palmitate, diisopropyladipate, isopropyl palmitate, octyl palmitate, isopropyl myristate,butyl myristate, glyceryl stearate, hexadecyl stearate, isocetylstearate, octyl stearate, octylhydroxy stearate, propylene glycolstearate, butyl stearate, decyl oleate, glyceryl oleate, acetylglycerides, the octanoates and benzoates of (C12-C15) alcohols, theoctanoates and decanoates of alcohols and polyalcohols such as those ofglycol and glycerol, and ricin- oleates of alcohols and poly alcoholssuch as those of isopropyl adipate, hexyl laurate, octyl dodecanoate,dimethicone copolyol, dimethiconol, lanolin, lanolin alcohol, lanolinwax, hydrogenated lanolin, hydroxylated lanolin, acetylated lanolin,petrolatum, isopropyl lanolate, cetyl myristate, glyceryl myristate,myristyl myristate, myristyl lactate, cetyl alcohol, isostearyl alcoholstearyl alcohol, and isocetyl lanolate, and the like.

Emulsifiers

Emulsifiers (i.e., emulsifying agents) are also used in certain aspectsof the invention in amounts effective to provide uniform blending ofingredients of the composition. Useful emulsifiers include (i) anionicssuch as fatty acid soaps, e.g., potassium stearate, sodium stearate,ammonium stearate, and triethanolamine stearate; polyol fatty acidmonoesters containing fatty acid soaps, e.g., glycerol monostearatecontaining either potassium or sodium salt; sulfuric esters (sodiumsalts), e.g., sodium lauryl 5 sulfate, and sodium cetyl sulfate; andpolyol fatty acid monoesters containing sulfuric esters, e.g., glycerylmonostearate containing sodium lauryl sulfate; (ii) cationics chloridesuch as N(stearoyl colamino formylmethyl) pyridium; N-soya-N-ethylmorpholinium ethosulfate; alkyl dimethyl benzyl ammonium chloride;diisobutylphenoxytheoxyethyl dimethyl benzyl ammonium chloride; andcetyl pyridium chloride; and (iii) nonionics such as polyoxyethylenefatty alcohol ethers, e.g., monostearate; polyoxyethylene laurylalcohol; polyoxypropylene fatty alcohol ethers, e.g., propoxylated oleylalcohol; polyoxyethylene fatty acid esters, e.g., polyoxyethylenestearate; polyoxyethylene sorbitan fatty acid esters, e.g.,polyoxyethylene sorbitan monostearate; sorbitan fatty acid esters, e.g.,sorbitan; polyoxyethylene glycol fatty acid esters, e.g.,polyoxyethylene glycol monostearate; and polyol fatty acid esters, e.g.,glyceryl monostearate and propylene glycol monostearate; and ethoxylatedlanolin derivatives, e.g., ethoxylated lanolins, ethoxylated lanolinalcohols and ethoxylated cholesterol.

Surfactants

Surfactants are also used in certain compositions of the invention.Suitable surfactants may include, for example, those surfactantsgenerally grouped as cleansing agents, emulsifying agents, foamboosters, hydrotropes, solubilizing agents, suspending agents andnonsurfactants (facilitates the dispersion of solids in liquids).

The surfactants are usually classified as amphoteric, anionic, cationicand nonionic surfactants. Amphoteric surfactants include acylamino acidsand derivatives and N-alkylamino acids. Anionic surfactants include:acylamino acids and salts, such as, acylglutamates, acylpeptides,acylsarcosinates, and acyltaurates; carboxylic acids and salts, such as,alkanoic acids, ester carboxylic acids, and ether carboxylic acids;sulfonic acids and salts, such as, acyl isethionates, alkylarylsulfonates, alkyl sulfonates, and sulfosuccinates; sulfuric acid esters,such as, alkyl ether sulfates and alkyl sulfates. Cationic surfactantsinclude: alkylamines, alkyl imidazolines, ethoxylated amines, andquaternaries (such as, alkylbenzyldimethylammonium salts, alkylbetaines, heterocyclic ammonium salts, and tetra alkylammonium salts).And nonionic surfactants include: alcohols, such as primary alcoholscontaining 8 to 18 carbon atoms; alkanolamides such as alkanolaminederived amides and ethoxylated amides; amine oxides; esters such asethoxylated carboxylic acids, ethoxylated glycerides, glycol esters andderivatives, monoglycerides, polyglyceryl, esters, polyhydric alcoholesters and ethers, sorbitan/sorbitol esters, and triesters of phosphoricacid; and ethers such as ethoxylated alcohols, ethoxylated lanolin,ethoxylated polysiloxanes, and propoxylated polyoxyethylene ethers.

Waxes

Suitable waxes which are useful in accord with the invention include:animal waxes, such as beeswax, spermaceti, or wool wax (lanolin); plantwaxes, such as carnauba or candelilla; mineral waxes, such as montan waxor ozokerite; and petroleum waxes, such as paraffin wax andmicrocrystalline wax (a high molecular weight petroleum wax). Animal,plant, and some mineral waxes are primarily esters of a high molecularweight fatty alcohol with a high molecular weight fatty acid. Forexample, the hexadecanoic acid ester of tricontanol is commoniy reportedto be a major component of beeswax.

Other suitable waxes according to the invention include the syntheticwaxes including polyethylene polyoxyethylene and hydrocarbon waxesderived from carbon monoxide and hydrogen.

Representative waxes also include: ceresin; cetyl esters; hydrogenatedjoioba oil; hydrogenated jojoba wax; hydrogenated rice bran wax; Japanwax; jojoba butter; jojoba oil; jojoba wax; munk wax; montan acid wax;ouricury wax; rice bran wax; shellac wax; sufurized jojoba oil;synthetic beeswax; synthetic jojoba oils; trihydroxystearin; cetylalcohol; stearyl alcohol; cocoa butter; fatty acids of lanolin; mono-,di- and25 triglycerides which are solid at 25° C., e..g., glyceyltribehenate (a triester of behenic acid and glycerine) and C1g-C36 acidtriglyceride (a mixture of triesters of C1g-C36 carboxylic acids andglycerine) available from Croda, Inc., New York, N.Y. under thetradenames Syncrowax HRC and Syncrowax HGL-C, respectively; fatty esterswhich are solid at 25° C.; silicone waxes such asmethyloctadecaneoxypolysiloxane and poly (dimethylsiloxy)stearoxysiloxane; stearyl mono- and diethanolamide; rosin and itsderivatives such as the abietates of glycol and glycerol; hydrogenatedoils solid at 25° C.; and sucroglycerides. Thickeners (viscosity controlagents) which may be used in effective amounts in aqueous systemsinclude: algin; carbomers such as carbomer 934, 934P, 940 and 941;cellulose gum; cetearyl alcohol, cocamide DEA, dsxtrin; gelatin;hydroxyethylcellulose; hydroxypropylcellulose; hydroxypropylmethylcellulose; magnesium aluminum silicate; myristyl alcohol; oatflour; oleamide DEA; oleyl alcohol; PEG-7M; PEG-14M; PEG-9OM; stearamideDEA; Stearamide MEA; stearyl alcohol; tragacanth gum; wheat starch;xanthan gum; and the like in the above list of thickeners, DEA isdiethanolamine, and MEA is monoethanolamine. Thickeners (viscositycontrol agents) which may be used in effective amounts in nonaqueoussystems include, aluminum stearates; beeswax; candelilla wax; carnauba;ceresin; cetearyl alcohol; cetyl alcohol; cholesterol; hydrated silica;hydrogenated castor oil; hydrogenated cottonseed oil; hydrogenatedsoybean oil; hydrogenated tallow glyceride; hydrogenated vegetable oil;hydroxypropyl cellulose; lanolin alcohol; myristyl alcohol; octytdodecylstearoyl sulfate; oleyl alcohol; ozokerite; microcystalline wax;paraffin; pentaerythrityl tetraoctanoate; polyacrylamide; polybutene;polyethylene; propylene glycol dicaprylate; propylene glycoldipelargonate; stearalkonium hectorite; stearyl alcohol; stearylstearate; synthetic beeswax; trihydroxystearin; trilinolein; tristearin;zinc stearate; and the like.

Film Formers

Suitable film formers which are used in accord with the invention keepthe composition smooth and even and include, without limitation:acrylamide/sodium acrylate copolymer; ammonium acrylates copolymer;Balsam Peru; cellulose gum; ethylene/maleic anhydride copolymer;hydroxyethylcellulose; hydroxypropylcellulose; polyacrylamide;polyethylene; polyvinyl alcohol; pvm/MA copolymer (polyvinylmethylether/maleic anhydride); PVP (polyvinylpyrrolidone); maleicanhydride copolymer such as PA-18 available from Gulf Science andTechnology; PVP/hexadecene copolymer such as Ganex V-216 available fromGAF Corporation; acryliclacrylate copolymer; and the like.

Generally, film formers can be used in amounts of about 0.1% to about10% by weight of the total composition with about 1% to about 8% beingpreferred and about 0.1°/O to about 5% being most preferred. Humectantscan also be used in effective amounts, including: fructose; glucose;glulamic acid; glycerin; honey; maltitol; methyl gluceth-10; methylgluceth-20; propylene glycol; sodium lactate; sucrose; and the like.

Preservatives

Preservatives according to certain compositions of the inventioninclude, without limitation: butylparaben; ethylparaben; imidazolidinylurea; methylparaben; O-phenylphenol; propylparaben; quaternium-14;quaternium-15; sodium dehydroacetate; zinc pyrithione; and the like.

The preservatives are used in amounts effective to prevent or retardmicrobial growth. Generally, the preservatives are used in amounts ofabout 0.1% to about 1% by weight of the total composition with about0.1% to about 0.8% being preferred and about 0.1% to about 0.5% beingmost preferred.

Perfumes

Perfumes (fragrance components) and colorants (coloring agents) wellknown to those skilled in the art may be used in effective amounts toimpart the desired fragrance and color to the compositions of theinvention.

Other ingredients which can be added or used in amounts effective fortheir intended use, including: biological additives to enhanceperformance or consumer appeal such as amino acids, proteins, vanilla,aloe extract, bioflavinoids, and the like; buffering agents, chelatingagents such as EDTA; emulsion stabilizers; pH adjusters; opacifyingagents; and propellants such as butane carbon dioxide, ethane,hydrochlorofluorocarbons 22 and 142b, hydrofluorocarbon 152a, isobutane,isopentane, nitrogen, nitrous oxide, pentane, propane, and the like.

The ingredients described above--sunscreening agents, emollients,emulsifiers, surfactants, solvents for sunscreening agents, waxes,thickeners, film formers, humectants, preservatives, surfactants,perfumes, coloring agents, biological additives, buffering agents,chelating agents, emulsion stabilizers, opacifying agents, pH adjusters,and propellants--are well known to those skilled in the art. Thedetermination of which ingredients to use to obtain the intendedformulations, and the determination of the amounts which may be used toachieve the intended functions and effects of these ingredients are wellwithin the capabilities of those skilled in the art without the need forundue experimentation. Further information may be obtained on theseingredients, for example, by reference to: Cosmetics & Toiletries, Vol.102, No. 3, March 1987; Balsam, M. S., et al., editors, CosmeticsScience and Technology, 2nd edition, Vol. 1, pp 27-104 and 179-222Wiley-Interscience, New York, 1972; Cosmetics & Toiletries, Vol. 104, pp67-111, February 1989; Cosmetics & Toiletries, Vol. 103, No. 12, pp100-129, December 1988; Nikitakis, J. M., editor, CTFA CosmeticIngredient Handbrook, First Edition, published by The Cosmetic, Toiletryand Fragrance Association, Inc., Washington, D.C., 1988; Mukhtar, H,editor, Pharmacology of the Skin, CRC Press 1992; and Green; F J, TheSigma-Aldrich Handbook of Stains, Dyes and Indicators., Aldrich ChemicalCompany, Milwaukee Wis., 1991.

A representative lotion formulation is listed below in Table 1, which isbroken into three parts.

                  TABLE 1                                                         ______________________________________                                        TYPICAL LOTION FORMULA                                                        Part 1                                                                        lanolin                  0.2-1%                                               cocoa butter             2.0-5%                                               emcol RHT (glycelyl slearate).sup.1                                                                    2.0-4%                                               hystren˜5016 (stearic acid).sup.2                                                                2.0-4%                                               vitamin E acetate        0.1-0.5%                                             aloe vera lipo quinone extract                                                                         0.1-1.0%                                             jojoba o                 0.1-1.0%                                             mineral oil              1.0-7%                                               propylparaben            0.1-1%                                               medical fluid 360 (dimethicone).sup.3                                                                  0.1-1%                                               ______________________________________                                        Part 2                                                                        water                    40-60%                                               carbopol 941 (1%) (polyacrylic acid polymer).sup.4                                                     10-35%                                               propylene glycol         2.0-7%                                               triethanolamine 99%      0.1-3%                                               lanogel 41 (PEG-75 lanolin).sup.5                                                                      0.25-1%                                              methylparaben            0.1-0.5%                                             sequestrene Na2          0.01-0.08%                                           ______________________________________                                        Part 3                                                                        perfume                  0.01-.5%                                             ______________________________________                                    

Footnotes

1. Witco Corp., Organics Division, NY, N.Y. (also Witconol RHT)

2. Humko Chemcal, Memphis, Tenn.

3. Dow Corning Corp., Midland, Mich.

4. B.F. Goodrich Specially Polymers and Chemical Division, Cleveland,Ohio

5. Amerchol Corp., Edison, N.J.

To make the formulation listed in Table 1, parts 1 and 2 are heatedseparately to 180° F. Part 1 is then added to Part 2. The resultantblend is cooled to 120° F. and Part 3 is then added.

Other examples of formulations which are useful according to theinvention include oil-in-water creams, oil-in-water lotions,water-in-oil lotions, oil-in-water resistant creams and lotions, sticks,gels, oils and mousses. Such formulations are found, for example, inCosmetics & Toiletries, Vol. 102, pp 117-130, March 1987, the disclosureof which is incorporated herein by reference.

Still other examples of formulations which are useful according to theinvention include hand and body lotions, oil-in-water emollient creams,moisturizing lotions, after sun emollient stick, facial spray mist, skinmousse and moisturizing gel. Such formulations are found, for example,in Cosmetics & Toiletries, Vol. 102, pp 47-160, April 1987, thedisclosure of which is incorporated herein by reference.

Those skilled in the art will appreciate that the formulations describedin the above cited Cosmetics & Toiletries references (March and April1987) represent types of formulations which may be suitably modified toallow for the addition of color indicators, and that such modificationsmay be accomplished without the need for undue experimentation.

The CIs according to the invention include several distinct compounds,including the following:

PHENOLPHTHALEIN

3,3-Bis(4-hydroxyphenyl)-1(3H0-isobenzofuranone .3.3-Bis(4-hydroxyphenyl)phthalide

Mol. Form.: C₂₀ H₁₄ O₄

F.W.: 318.33

Appearance: White powder

Solubility: H2O 1 mg/ml

EGME 100 mg/ml

ETOH 30 mg/ml

Phenolphthalein, 3,3-Bis(4-hydroxyphenyl)-1(3H0-isobenzofuranone.3.3-Bis(4-hydroxyphenyl)phthalide, a preferred acid-base indicator according tothe invention, is made by condensing one mole of phthalic anhydride withtwo moles of phenol. The condensation product is usually isolated as thecolorless lactone form. The disodium salt form is red due to the openingof the lactone rine and the concomitant paraquinoid-chromophoreformation. However, with the addition of enough sodium hydroxide to formthe trisodium carbinol salt, it becomes colorless again due to theelimination of the paraquinoidal structure.

σ-CRESOLPHTHALEIN: 3,3-Dimethylphenolphthalein

Mol. Form.: C₂₂ H₁₈ O₄

F.W: 346.38

Appearance: Beige powder

Solubility: H2O 1 mg/ml

EGME 90 mg/ml

ETOH 50 mg/ml

σ-Cresolphthalein, 3,3-Dimethylphenolphthalein, is a member of thephthalein-indicator series and is made by condensing one mole ofphthalic anhydride with two moles of s-cresol. This white,crystalline-powder product is soluable in alcohol and aqueous alkalisolutions and very slightly soluable in water. An acid-base indicator,it has a visual-transition interval extending from pH 8.2 (colorless) topH 9.8 (red) and a pK of 9.4.

THYMOLPHTHALEIN

Mol. Formula: C₂₈ H₃₀ O₄

F.W.: 430.54

Appearance: White powder

Solubility: H2O 1 mg/ml

EGME 100 mg/ml

ETOH 70 mg/ml

Thymolphthalein is a hydroxytriarylmethane indicator that is made bycondensing two moles of thymol with one mole of phthalic anhydride inthe presence of heat and a condensing agent, such as stannin chloride.It is soluble in the lower aliphatic alcohols, acetone and dilutealkalies. It has a visual-transition interval of pH 8.8 (colorless) topH 10.5 (blue).

Fluorescent Indicator

COUMARIN

Mol. Formula: C₉ H₆ O₂

F.W.: 146.15

Appearance: White crystalline powder

Solubility: H2O <0.1 mg/ml

EGME <0.1 mg/ml

ETHOL <0.1 mg/ml

Coumarin is used as a fluorescent indicator displaying afluorecent-transition interval of pH 8.0 (colorless) to pH 9.5 (green).

Other fluorescent indicators according to the invention include: (1)2,3, dioxyxanthone with a transition interval pH 5.4 (colorless) to pH7.6 blue/violet; and (ii) coumeric acid with a transition interval pH7.2 (colorless) to pH 7.5 (blue).

Other nonfluorecent indicators according to the invention include: (i)6.8-dinitro-2,4-(1H) quinazolinedione with a transition interval pH 6.4(colorless) to pH 8.0 (yellow); and (ii) ethyl-bis (2,4-dimethylphenyl)ethanoate with a transition interval pH 8.4 (colorless) to pH 9.6(Blue).

FIG. 1 illustrates a typical use of the invention. Specifically, FIG. 1shows a human arm 10 with a visible and evenly distibuted application ofsunscreen lotion 12, constructed according to the invention, applied toa section 14 of the arm 10. The section 14 is visible because of the pHindicator described herein. FIG. 1 also shows the same arm 10' after ashort time period--e.g., between about 0.5 and 10 minutes, andpreferably about one minute--and wherein the arm 10' is substantiallythe normal color of human skin.

FIG. 2 shows a graph illustrating the effects of indicator concentrationon the time course of CI change from visible to clear. Specifically, aphenolphthalein color indicator was dissolved in phosphate bufferedsaline at the indicated concentration and applied to a subjects skin.The time from application to the complete change in color was measuredand recorded. The bars indicate the mean time of three trials.

FIG. 3 shows a graph illustrating the effect of concentration on a CIchange from visible to clear when dissolved in a common sunscreen in tenvolunteers. The concentrations were 20 and 50 mg/ml. Specifically, inFIG. 3, the time of color change (on the vertical axis) at twoconcentrations of phenolthalien dissolved in a common sunscreen wasmeasured on the forearms of ten separate volunteers. Variability wasexpected and observed. A concentration of 50 mg/ml provided the mostconsistant results of the indicator changing from visible to colorlessin 1-2 minutes.

FIG. 4 is a diagrammatic representation of an apparatus according to theinvention. Specifically, FIG. 4 shows a cap 100 constructed according tothe invention. The cap 100 contains a color indicator 102 and includes athreading portion 104 (illustrated as an outline because the threads areinternal to the illustrated view) which can attach, via a threading orscrew action, onto a lotion container 106 (specifically onto the topthreads 107). The lotion container 106 is of the prior art type known tothe public for containing lotions, creams, gels, mousses, sunscreenagents, and the like (collectively, the "lotion 108"). The inventioncolors the lotion 108 upon use by a user desirous of applying the lotion108 to the user's skin by mixing the color indicator 102 with the lotion108 during application. Accordingly, the lotion 108 appears colored uponapplication, but typically becomes colorless after a period of time onthe user's skin (depending upon the intended color of the lotion 108).

FIG. 4A illustrates further features of the cap 100. Specifically, FIG.4A shows a cutaway side view of the cap 100 with threading portion 104used to attach the cap 100 to a container, e.g., the container 106 ofFIG. 4. A conduit 110 provides a path for the lotion to pass through thecap 100 to the user's skin, while a top seal 112 selectively seals thecap 100, and hence the lotion, so that the lotion 108 is safely sealedwhile not in use. Such a cap is known to those skilled in the art.

FIG. 4A also illustrates a twist portion 114 which provides a user witha mechanism to control the flow of color indicator to the conduit 110. Auser selectively twists the top portion 114 while keeping the lowerportion 116 still to adjust the overlapping flow holes 118. These flowholes 118, shown in FIG. 4B, provide varying flow diameters between thecavity 120, containing the color indicator 102, and the conduit 110.Accordingly, a user can adjust the amount of color added to the lotionupon application, from No Flow (i.e., no color), to Small Flow (i.e,some color), to Large Flow (i.e., maximum color), such as illustrated inFIG. 4B.

It is accordingly intended that all matter contained in the abovedescription or shown in the accompanying drawings be interpreted asillustrative rather than in a limiting sense.

It is also intended that the following claims cover all of the genericand specific features of the invention as described herein, and allstatements of the scope of the invention which, as a matter of language,might be said to fall there between.

Having described the invention, what is claimed as new and secured byLetters Patent is:
 1. A composition for application to human skin,comprising a sunscreen formulation and a physiologically compatiblecolor indicator, the color indicator being mixed with the sunscreenformulation to form a mixture that has a visible color when applied tothe skin, and that has substantially no color when distributed evenlyover the skin.
 2. A composition according to claim 1, wherein the colorindicator is selected from the group consisting essentially of a pHindicator and a coloring agent.
 3. A composition according to claim 2,wherein the coloring agent comprises a colorant which imparts a selectedcolor to the formulation.
 4. A composition according to claim 2, whereinthe pH indicator is selected from the group consisting essentially ofphenolphthalein, σ-cresolphthalein, thymolphthalein, quinazolinedione,ethyl-bis ethanoate, coumarin, dioxyxanthone, and 6.8-dinitro-2,4-(1H)quinazolinedione.
 5. A composition according to claim 2, wherein the pHindicator has substantially no visible color within a pH range of theskin, and which has a visible color outside the pH range, wherein themixture turns substantially colorless after prolonged contact with theskin.
 6. A composition according to claim 1, wherein the sunscreenformulation forms one of a lotion, gel, mousse, medication, cream,moisturizer, ointment, waxed base stick, aerosol, alcohol stick, oil,and mist for facilitating application to the skin.
 7. A compositionaccording to claim 1, wherein the sunscreen formulation comprises one ofUVA type sunscreen agent and UVB type sunscreen agent.
 8. A compositionaccording to claim 1, wherein the sunscreen formulation comprises aphysical sunscreening agent.
 9. In a method of forming a sunscreenformulation of the type comprising one of a lotion, gel, mousse,medication, cream, moisturizer, ointment, waxed base stick, aerosol,alcohol stick, oil, and mist, the improvement comprising the steps ofproviding a physiologically compatible color indicator and mixing theformulation with the color indicator so as to colorize the formulationfor application to human skin.
 10. In a method according to claim 9,wherein the step of providing a color indicator comprises the furtherimprovement of providing a pH indicator which has visible color outsidea pH range of the skin and which has substantially no visible color atthe pH of the skin.
 11. In a method according to claim 9, wherein thestep of providing a color indicator comprises the further improvement ofproviding a colorant to selectively add color to the formulation whereinthe formulation has visible color when applied to the skin.
 12. In amethod according to claim 9, the further improvement comprising the stepof sealing the formulation and color indicator within a lotion containerfor containing formulation and color indicator.
 13. A system forapplying colorized lotion to human skin, comprising a lotion within afirst container and a color indicator in a cap that connects to thefirst container, the cap having means for mixing the indicator with thelotion as a user ejects the lotion from the first container and throughthe cap.
 14. A system according to claim 13, wherein the color indicatorcomprises one of a colorant and a pH indicator.